Active clinical trials for "Optic Nerve Neoplasms"

Endotracheal intubation and laryngeal mask are generally applied to secure the airway during general anesthesia. There is a widespread opinion among anesthesiologists that endotracheal intubation increases intracranial pressure. Since there were no non-invasive methods measuring intracranial pressure in the past, adequate studies on this subject could not be done. With this measurement, we aimed to show whether ETT or LMA applications have effects on intracranial pressure.

The purpose of this study is to find out what effects (good and bad) CyberKnife stereotactic radiosurgery has on tumors near the critical structures of the eye (optic apparatus). The investigators hypothesize that hypofractionated stereotactic radiotherapy via the CyberKnife ® can deliver tumor ablating doses of radiation to perioptic lesions safely and effectively while sparing the adjacent optic apparatus and normal brain tissues from receiving damaging doses of radiation.

Traditional treatment options for optic nerve sheath meningiomas (ONSM) include observation, surgery and radiotherapy, but to date none of these has become the clear treatment of choice. The role of the radiotherapy remained uncertain because of the concern about radiation related optic neuropathy In the recent past two large series of patients treated with a fractionated stereotactic radiotherapy confirmed these positive experiences in tumour control and greatly reduced the concern about the treatment related toxicity. Under the light of successful meningiomas treatment, radiosurgery, had proposed as a treatment option. Single session, high conformality, frame based radiosurgery systems are seldom if ever proposed as ONSMs treatment due to the known dose tolerance of the optic nerve. The first experience in ONSMs treatment with multisession radiosurgery treatment was quite promising. The aim of the present study is to prospectively evaluate the efficacy and safety of multisession radiosurgery in ONSMs treatment. In order to evaluate multisession radiosurgery 50 patients will be enrolled in the present study. All patients will be treated by using multisession radiosurgery, with 5 fractions of 5 Gy each to a total dose of 25 Gy prescribed to the 75-85% isodose line. Patients were evaluated both for tumor growth control and visual function.